Kevin Zegers as Dick Grayson/Nightwing
Dick Grayson became Nightwing after he was dismissed from the role of Robin at eighteen. Grayson's Flamebird was Bette Kane. He was featured in a Nightwing series from 1996 to 2009; since Wayne's apparent death, Grayson has become the new Batman, subsequently retiring his Nightwing mantle. Zegers has the proper look of bad ass and leader needed for Nightwing. As a young rather unknown actor, he would do well as the leader of the crew. In the movie he would be a very serious leader that hates to be compared to Batman.
Ashley Greene as Starfire Koriand'r, Starfire's real name, is a princess of the planet Tamaran, and was in line to rule the planet as Queen. Komand'r ("commander", also known as Blackfire), her older sister, developed a bitter rivalry with her after suffering a disease in infancy that robbed her of the ability to harness solar energy to allow her to fly, and by extension, her right to the throne. This rivalry continued and intensified when the siblings were sent for warrior training with the Warlords of Okaara. Things came to a head during a sparring exercise in which Komand'r attempted to kill her sister. As a result, Komand'r was expelled and she swore vengeance. Greene is a very hot young actress with a lot of potential and the right look for the role of Starfire. In the Twilight movies her character is very similar to what Starfire should be. She would serve as the love interest for Nightwing.
Jamie Bell as Beast Boy As a child, Garfield contracts a rare illness by being bitten by a green monkey called Sakutia but then is saved by his parents who use an untested serum on him. This serum has the unintended effect of turning his skin and hair green and granting him the ability to metamorphose into any animal of his choice Bell is a very talented actor and has shown it in very different roles. He could bring the comedic and the athletic fighting side of Beast Boy. Beast Boy would be best friends with Cyborg and would serve as comedic relief for the movie. He would have a love for Terra that would keep him in denial of her being evil.
Rob Brown as Cyborg Victor Stone is the son of Silas and Elinore Stone, a pair of scientists who decide to use him as a test subject for various intelligence enhancement projects. When he visits his parents at work at S.T.A.R. Labs, an experiment in dimensional travel goes wrong when a massive gelatinous monster crosses over an experimental portal and kills Elinore. The creature then turns on Victor and severely mutilates him before Silas forces the creature back through the portal. To save his son, Silas outfits him with experimental prosthetics of his own design. However, the equipment cannot be worn inconspicuously, and thus Victor is horrified to see much of his body, including part of his face, replaced with sheer metallic limbs and implants. Brown has been in great roles ever since
Finding Forester. He is great at showing a serious intensity, and then showing the light hearted friend. He would be great as a friend to Beast Boy and a support to Robin when needed.
Kat Dennings as Raven In the latest relaunch title, Titans, Raven and a group of classmates are attacked by a demonic creature, sent by Raven's resurrected father, Trigon. She soon joins Beast Boy, Donna Troy, Red Arrow, Starfire, Flash, and Nightwing at New York's Titans Island, where Cyborg and his Teen Titans team were attacked by Deathstroke and the villainous Titans East. These events lead to the creation of the newest team of Titans, which consists of the original New Teen Titans. Dennings has been a much liked choice for this role and I completely agree. She could show the dark and mysterious side and the likeable side.
Paul Wesley as Red Arrow Speedy joined Robin, Kid Flash, Aqualad and Wonder Girl in the newly-formed Teen Titans, a group originally formed from the various "teen sidekicks" active in DC comics at that time. Speedy was initially a successful member and began dating Wonder Girl (Donna Troy). I originally casted Wesley as Speedy in my Green Arrow 2 story. I think he has the right attitude and bad ass look for the role of Speedy. In this role he would often fight against Robin for control over the group. Until the end where he decides to start a Titans East team. Red Arrow would hate when people call him Speedy.
Odette Yustman as Wonder Girl Wonder Woman's younger sister Wonder Girl made her first appearance in The Brave and the Bold #60 (July 1965) as a member of a "junior Justice League" called the Teen Titans, consisting of Robin (Dick Grayson), Kid Flash (Wally West), and Aqualad. After next being featured in Showcase #59 (December 1965), the Teen Titans were spun off into their own series with Teen Titans #1, cover-dated February 1966. Yustman is a very hot and very strong girl that would be perfect for an Amazon. She has acting talent for the role and would be great as Donna Troy. In the movie she would serve as a love interest for Red Arrow. In the end she would leave with him for Titans East.
Taylor Lautner as Aqualad Garth's origin is similar to that of his mentor. He is an amphibious humanoid who was left to die because of ancient Atlantean superstition and prophecy. Tempest is the prince and heir to the throne of the Idyllists, a colony of Atlanteans who settled in the Hidden Valley 4,000 years ago. There, nestled in the capital city of Shayeris (formerly Crastinus), the pacifist Idyllists became rabid builders and collectors, architects and artisans, and eschewed physical violence at all costs. The Idyllists were also practitioners of magic and kept an extensive library of mystical texts and scrolls. I know many will hate this pick, but I don’t think Lautner is that bad of an actor he just chose to be a part of a very popular franchise to better his career. And I think it was the right choice due to the movie offers he’s been given. He would be great as Aqualad, being a strong supporter of Red Arrow and the team. He would flirt with Raven and Starfire, making Nightwing jealous. At the end of the movie he joins Titans East.
Justin Chatwin as Kid Flash Cameo Suffering from a hyper-accelerated metabolism, Bart Allen was aging at a faster rate than that of any human being, thus causing him to appear the age of twelve when he was chronologically only two years old. To prevent him from developing mental health problems, he was raised in a virtual reality machine which created a simulated world that kept pace with his own scale of time. When it became clear that this method was not helping, his grandmother, Iris Allen, took him back in time to the present where The Flash, Wally West, tricked Bart into a race around the world. By forcing Bart into an extreme burst of speed, Wally managed to shock his hypermetabolism back to normal. Aside from the Dragonball movie, Chatwin has done very well in many good movies. He has the right comedic ability for the part of a young Bart Allen. He would serve as an after the credits cameo in the end when Red Arrow, Aqualad, and Wonder Girl go to Titans East. As they begin setting up their new base Bart walks in asking if the team has started recruiting new members yet.
Villians Stephen Lang as Deathstroke 
Lang was great in
AVATAR as the villain and in this he would also serve as the main villain. Except in this he would be more in the background as Terra serves as his minion. Nightwing would be on his tail throughout the movie and in the end they would have a heated fight.
Hayden Panettiere as Terra Terra became a mercenary, doing dirty work for others such as Deathstroke the Terminator. She joined the Teen Titans, fooling them by staging a battle against Deathstroke. She then operated as a spy for Deathstroke, eventually giving him the information he needed to kidnap the Titans. Hayden looks a lot like Terra and could be the hot girl that everyone thinks is cool, and then the double crossing person you hate. In this movie Terra would start on the team but the team pursues Deathstroke Nightwing finds out that Terra is working for him and then she starts attacking the team, almost killing Aqualad beneath a mountain of rubble.
So that’s my cast and the way the movie would go. The team would start going after Deathstroke, and after a while Nightwing would find out Terra works for him. This leads Red Arrow to question’s Nightwing’s ability to lead and his trust. In the end Nighwing would defeat Deathstroke but his body would be lost. Terra would end up being killed by Beast Boy, because he loves her so much he would rather have himself kill her than have anyone else do it. Then Red Arrow would lead a team to make the Titans East setting it up for a sequel or potential spin-off.
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